1. Field of the Invention
The present invention relates to self-sealing valves, and in particular, it relates to self-sealing valves for use in inflatable devices.
2. Description of the Prior Art
In recent developments in inflatable prosthetic devices, it has been found desirable to progressively inflate the prosthetic device over a period of time. This has required the use of subcutaneous injection sites connected to the inflatable prosthetic device by a fill tube. In addition, mammary prostheses having an inner chamber disposed within an outer chamber with the two chambers being filled with dissimilar fluids have become popular. Typically, the outer chamber is filled with a silicone gel prior to implantation and after the prosthesis has been implanted, a fill tube which extends through a valve in the outer chamber, through the outer chamber, and into the inner chamber through a second valve is used to fill the inner chamber with a saline solution.
The valve is typically made of two sheets of silicone rubber bonded together along their edges with a passage therebetween. If a fill tube is disposed within the valve for a long time, stresses in the silicone rubber forming the passage result in the valve not sealing adequately once the fill tube is removed. The passage becomes somewhat "set" in an open position and remains in the set open position once the fill tube has been removed.
A curling self-sealing valve is described in patent application Ser. No. 756,408, now U.S. Pat. No. 4,662,883, entitled, "Self-Sealing Valve for Fluid Fillable Device," filed on July 17, 1985, and assigned to the same assignee as the present application, provides a seal by curling along the longitudinal axis of the fill tube passage. This device has been on sale for more than one year prior to the filing date of the present application.
A number of patents directed to prosthetic inflatable devices show valves which are constructed of two sheets of silicone elastomer bonded together along two edges to form a passage. None of the valves illustrated in the immediately below-listed patents are constructed to avoid the passage being permanently deformed due to the stress caused on the material by the fill tube inserted into the passage over a long period of time:
______________________________________ Inventor U.S. Pat. No. ______________________________________ Hyans 4,459,318 Bejarano 4,263,682 Cox, Jr. 4,178,643 Koneke et al 3,852,833 McGhan et al 3,852,832 Valliancourt et al 3,565,078 Krueger 2,697,229 ______________________________________
The Lynch U.S. Pat. No. 3,883,902 and the Boone U.S. Pat. No. 3,600,718 show other types of valves used in inflatable prosthetic devices. The valve illustrated in the Lynch Patent shows a complicated sealing arrangement and the valve shown in the Boone Patent shows a valve using a silicone gel chamber as a sealing arrangement.
Still other patents show inflatable devices other than prosthetic devices using a variety of valving arrangements for the introduction of air. However, similar to the patents directed to prosthetic devices, the valves shown in the immediately below-listed patents are also not designed for the retention of a fill tube for a long period of time.
______________________________________ Inventor U.S. Pat. No. ______________________________________ Kampa 3,584,671 Mirando 3,523,563 Mondano 3,410,300 Nicholls 3,204,959 Siedow 2,933,120 Orms 2,795,425 Andrews 2,568,976 Goldsmith et al 1,551,099 ______________________________________ Foreign Patents Inventor (Country) Patent No. ______________________________________ Ingram (British) 9,698 ______________________________________